Data Views to Route All Requests, Irrespective of
the Target DN of the Request

This section describes a data view that routes all requests to a data
source pool, irrespective of the target DN of the request. This data view
is called the root data view. The root data view is
created by default when an instance of Directory Proxy Server is created.

The example in this section has multiple data sources that contain the
same set of subtrees. The data sources are data-equivalent and pooled into
one data source pool for load balancing. A data view is configured with a
base DN at the rootDSE, represented as “ ”. Figure 17–3 shows an example deployment.

Figure 17–3 Example Deployment That Routes All Requests to a
Data Source Pool, Irrespective of the Target DN

Because the base DN of the data view is the rootDSE, the data view encompasses
the base DN of all possible requests. All requests are
forwarded to the data source pool, irrespective of the target DN or whether
the data source contains an entry for the request.

If Directory Proxy Server receives a request with a target DN that does
not exist in the data source, the request is forwarded to the data source
pool. The data source that responds to the request returns an error.

Data Views to Route Requests When a List of Subtrees
Are Stored on Multiple, Data-Equivalent Data Sources

This section describes data views that route requests targeted at a
list of subtrees to a set of data-equivalent data sources.

The example in this section has multiple data sources that each contain
the same set of subtrees. The data sources are data-equivalent and pooled
into one data source pool for load balancing. A data view is configured for
each subtree to expose that subtree to client requests. Figure 17–3 shows the example deployment.

Figure 17–4 Example Deployment That Routes Requests When a List
of Subtrees Is Stored on Multiple, Data-Equivalent Data Sources

A request is exposed to a data view only if the target DN is subordinate
to the base DN of the data view. When a request is exposed to a data view,
the request is forwarded to the data source pool specified by the data view.

If the target DN of a request is not subordinate to the base DN of any
data view, Directory Proxy Server returns an error.

In Figure 17–4, requests
that target dc=example1,dc=com or dc=example2,dc=com are
forwarded to the data source pool. Directory Proxy Server returns an error for
requests that target neither dc=example1,dc=com nor dc=example2,dc=com.

Data Views to Provide a Single Point of Access When
Different Subtrees Are Stored on Different Data Sources

This section describes how Directory Proxy Server provides a single point
of access to different subtrees of data on multiple data sources. The example
in this section contains a data view is for each subtree, to expose that subtree
to client requests. A data source pool is configured for each set of data-equivalent
data sources. Figure 17–5 shows
the example deployment.

Figure 17–5 Example Deployment That Provides a Single Point
of Access When Different Subtrees Are Stored on Different Data Sources

The Directory Proxy Server exposes a request to a data view if the DN targeted
by the request is subordinate to the base DN of the data view. When a request
is exposed to a data view, the request is forwarded to the data source pool
specified by the data view.

If a request has a target DN that is not subordinate to the base DN
of a data view, Directory Proxy Server returns an error.

In Figure 17–5, client requests
that target dc=example1,dc=com are forwarded to the data
source pool 1 and are treated by data source 1 or data source 1'. Client requests
that target dc=example2,dc=com are forwarded to the data
source pool 2 and are treated by data source 2 or data source 2'. The Directory Proxy Server returns
an error for client requests that target neither dc=example1,dc=com nor dc=example2,dc=com.

Data Views to Route Requests When Different Parts
of a Subtree Are Stored in Different Data Sources

This section describes how Directory Proxy Server provides a single point
of access to different parts of a subtree stored in multiple data sources.
To route requests for different parts of a subtree, Directory Proxy Server uses
a distribution algorithm. In the example in this section, Directory Proxy Server uses
the numeric distribution algorithm. For more information about distribution
algorithms, see Distributing Entries In a Subtree to Different Data Views.

The example in this section contains two data views with the same base
DN. A numeric distribution algorithm is used to separate entries into different
data views. A data source pool is configured for each set of data-equivalent
data sources. Figure 17–6 shows
the example deployment.

Figure 17–6 Example Deployment That Routes Requests When Different
Parts of a Subtree Are Stored in Different Data Sources

Directory Proxy Server exposes a request to the data view which satisfies
the following conditions:

The DN targeted by the request is subordinate to the base
DN of the data view

The parameters of the requests match the pattern specified
by the distribution algorithm in the data view

When a request is exposed to a data view, the request is forwarded to
the data source pool specified by the data view.

If a request that does not match the conditions of any data view, Directory Proxy Server returns
an error.

The example in Figure 17–7 contains
three data views. The base DN of dataview–1 is superior
to the base DNs of dataview-2 and dataview-3.

The excluded-subtrees property on dataview-1 excludes dataview-2 and dataview-3 from dataview-1.
The alternate-search-base-dn properties on dataview-2 and dataview-3 include dataview-2 and dataview-3 in search operations targeted at dataview-1. Figure 17–7 shows the example deployment.

Figure 17–7 Example Deployment to Route Requests When Superior
and Subordinate Subtrees Are Stored in Different Data Sources

Directory Proxy Server exposes a request to the data view which satisfies
the following conditions:

The DN targeted by the request is subordinate to the base
DN of the data view

The DN targeted by the request is not excluded from the data
view by the excluded-subtrees parameter

When a request is exposed to a data view, the request is forwarded to
the data source pool specified by the data view.

If a request does not match the conditions of any data view, the request
cannot be exposed to a data view and Directory Proxy Server returns an error.

In Figure 17–7, client requests
that target dc=example,dc=com but do not target ou=computer,
dc=example, dc=com or ou=people, dc=example, dc=com are
forwarded to the data source pool 1. Such requests are treated by data source
1 or data source 1'. Client requests that target ou=computer, dc=example,
dc=com or ou=people, dc=example, dc=com are forwarded
to data source pool 2 and data source 3, respectively. Directory Proxy Server returns
an error for client requests that do not target dc=example,dc=com.

All three data views are candidates for search operations that are targeted
at dc=example,dc=com.

Data Views With Hierarchy and a Distribution Algorithm

Different data views can be used in the same topology to expose or hide
parts of a subtree. Figure 17–8 shows
are an example with data views that combine the hierarchy shown in Figure 17–7 with the distribution algorithms
shown in Figure 17–6.

The example in Figure 17–8 contains
four data views. The base DN of data view 1 is superior to the base DNs of
the other data views. Data view 3 and data view 4 have the same base DN, but
a numeric distribution algorithm separates entries into the different data
views. Figure 17–8 shows the example
deployment.

Figure 17–8 Data View With Hierarchy and a Distribution Algorithm

The excluded-subtrees property on dataview-1 excludes
the other data views from dataview-1. The alternate-search-base-dn property on dataview-2, dataview-3,
and dataview-4 includes these data views in search operations
targeted at dataview-1.

Directory Proxy Server exposes a request to the data view which satisfies
the following conditions:

The DN targeted by the request is subordinate to the base
DN of the data view

The DN targeted by the request is not excluded from the data
view by the excluded-subtrees parameter

The parameters of the requests match the pattern specified
by the distribution algorithm

When a request is exposed to a data view, the request is forwarded to
the data source pool specified by the data view.

If a request does not match the conditions of any data view, Directory Proxy Server returns
an error.